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941.
Ryan Schram 《The Australian journal of anthropology》2019,30(1):18-34
Western ideologies of imperialism conceptualise time as heterogeneous in that they assume that colonised lands are outside of historical time. In this respect, the discursive construction of an empty frontier has been crucial to colonial dispossession. Yet colonial discourses become dominant through their circulation, and so the savage spaces they imagine take on a life of their own when they are revoiced. Papuan Times, a newspaper published by graduates of an industrial mission school at Kwato Island in the colonial Territory of Papua and New Guinea after the Second World War, produces subaltern agency in its reports on the pacification of the Highlands. While its news articles reproduce the heterogeneous chronotope of colonial discourse, articles describing the missionary work of former Kwato students in the Highlands reimagine the Highlands frontier as a horizon of social transformation. The Papuan Times strategy reflects the fact that a community's pursuit of the good exists in relation to others which constrain it, and, more generally, that an anthropology of the good is also an anthropology which recognises the fraught coexistence of a plurality of values. 相似文献
942.
943.
Lasha Gogokhia Kate Buhrke Rickesha Bell Brenden Hoffman D. Garrett Brown Christin Hanke-Gogokhia Nadim J. Ajami Matthew C. Wong Arevik Ghazaryan John F. Valentine Nathan Porter Eric Martens Ryan O’Connell Vinita Jacob Ellen Scherl Carl Crawford W. Zac Stephens Sherwood R. Casjens June L. Round 《Cell host & microbe》2019,25(2):285-299.e8
944.
Lou Brossette Joël Meunier Simon Dupont Anne‐Genevive Bagnres Christophe Lucas 《Ecology and evolution》2019,9(1):192-200
Parental care is a major component of reproduction in social organisms, particularly during the foundation steps. Because investment into parental care is often costly, each parent is predicted to maximize its fitness by providing less care than its partner. However, this sexual conflict is expected to be low in species with lifelong monogamy, because the fitness of each parent is typically tied to the other's input. Somewhat surprisingly, the outcomes of this tug‐of‐war between maternal and paternal investments have received important attention in vertebrate species, but remain less known in invertebrates. In this study, we investigated how queens and kings share their investment into parental care and other social interactions during colony foundation in two termites with lifelong monogamy: the invasive species Reticulitermes flavipes and the native species R. grassei. Behaviors of royal pairs were recorded during six months using a non‐invasive approach. Our results showed that queens and kings exhibit unbalanced investment in terms of grooming, antennation, trophallaxis, and vibration behavior. Moreover, both parents show behavioral differences toward their partner or their descendants. Our results also revealed differences among species, with R. flavipes exhibiting shorter periods of grooming and antennation toward eggs or partners. They also did more stomodeal trophallaxis and less vibration behavior. Overall, this study emphasizes that despite lifelong monogamy, the two parents are not equally involved in the measured forms of parental care and suggests that kings might be specialized in other tasks. It also indicates that males could play a central, yet poorly studied role in the evolution and maintenance of the eusocial organization. 相似文献
945.
946.
947.
Joel Ralston Lydia Lorenc Melissa Montes William V. DeLuca Jeremy J. Kirchman Bradley K. Woodworth Stuart A. Mackenzie Amy Newman Hilary A. Cooke Nikole E. Freeman Alex O. Sutton Lila Tauzer D. Ryan Norris 《Ecology and evolution》2019,9(15):8840-8855
Migratory behaviors such as the timing and duration of migration are genetically inherited and can be under strong natural selection, yet we still know very little about the specific genes or molecular pathways that control these behaviors. Studies in candidate genes Clock and Adcyap1 have revealed that both of these loci can be significantly correlated with migratory behaviors in birds, though observed relationships appear to vary across species. We investigated geographic genetic structure of Clock and Adcyap1 in four populations of blackpoll warblers (Setophaga striata), a Neotropical–Nearctic migrant that exhibits geographic variation in migratory timing and duration across its boreal breeding distribution. Further, we used data on migratory timing and duration, obtained from light‐level geolocator trackers to investigate candidate genotype–phenotype relationships at the individual level. While we found no geographic structure in either candidate gene, we did find evidence that candidate gene lengths are correlated with five of the six migratory traits. Maximum Clock allele length was significantly and negatively associated with spring arrival date. Minimum Adcyap1 allele length was significantly and negatively associated with spring departure date and positively associated with fall arrival date at the wintering grounds. Additionally, we found a significant interaction between Clock and Adcyap1 allele lengths on both spring and fall migratory duration. Adcyap1 heterozygotes also had significantly shorter migration duration in both spring and fall compared to homozygotes. Our results support the growing body of evidence that Clock and Adcyap1 allele lengths are correlated with migratory behaviors in birds. 相似文献
948.
949.
Gregory M. Chorak Carl R. Ruetz Ryan A. Thum Charlyn G. Partridge David J. Janetski Tomas O. Hk David F. Clapp 《Ecology and evolution》2019,9(16):8922-8932
Maintenance of genetic and phenotypic diversity is widely recognized as an important conservation priority, yet managers often lack basic information about spatial patterns of population structure and its relationship with habitat heterogeneity and species movement within it. To address this knowledge gap, we focused on the economically and ecologically prominent yellow perch (Perca flavescens). In the Lake Michigan basin, yellow perch reside in nearshore Lake Michigan, including drowned river mouths (DRMs)—protected, lake‐like habitats that link tributaries to Lake Michigan. The goal of this study was to examine the extent that population structure is associated with Great Lakes connected habitats (i.e., DRMs) in a mobile fish species using yellow perch as a model. Specifically, we tested whether DRMs and eastern Lake Michigan constitute distinct genetic stocks of yellow perch, and if so, whether those stocks migrate between the two connected habitats throughout the year. To do so, we genotyped yellow perch at 14 microsatellite loci collected from 10 DRMs in both deep and littoral habitats during spring, summer, and autumn and two nearshore sites in Lake Michigan (spring and autumn) during 2015–2016 and supplemented our sampling with fish collected in 2013. We found that yellow perch from littoral‐DRM habitats were genetically distinct from fish captured in nearshore Lake Michigan. Our data also suggested that Lake Michigan yellow perch likely use deep‐DRM habitats during autumn. Further, we found genetic structuring among DRMs. These patterns support hypotheses of fishery managers that yellow perch seasonally migrate to and from Lake Michigan, yet, interestingly, these fish do not appear to interbreed with littoral fish despite occupying the same DRM. We recommend that fisheries managers account for this complex population structure and movement when setting fishing regulations and assessing the effects of harvest in Lake Michigan. 相似文献
950.
Mathieu Santonja Anne Bousquet‐Mlou Stphane Greff Elena Ormeo Catherine Fernandez 《Ecology and evolution》2019,9(14):8201-8213
The Mediterranean region is recognized as a global biodiversity hotspot. However, over the last decades, the cessation of traditional farming in the north part of the Mediterranean basin has given way to strong afforestation leading to occurrence of abandoned agricultural lands colonized by pioneer expansionist species like Pinus halepensis. This pine species is known to synthesize a wide range of secondary metabolites, and previous studies have demonstrated strong allelopathic potentialities of its needle and root leachates. Pinus halepensis is also recognized to release significant amounts of volatile organic compounds (VOC) with potential allelopathic effects that have never been investigated. In this context, the objectives of the present study were to improve our knowledge about the VOC released from P. halepensis needles and roots, determine if these VOC affect the seed germination and root growth of two herbaceous target species (Lactuca sativa and Linum strictum), and evaluate if soil microorganisms modulate the potential allelopathic effects of these VOC. Thirty terpenes were detected from both, needle and root emissions with β‐caryophyllene as the major volatile. Numerous terpenes, such as β‐caryophyllene, δ‐terpinene, or α‐pinene, showed higher headspace concentrations according to the gradient green needles < senescent needles < needle litter. Seed germination and root growth of the two target species were mainly reduced in presence of P. halepensis VOC. In strong contrast with the trend reported with needle leachates in literature, we observed an increasing inhibitory effect of P. halepensis VOC with the progress of needle physiological stages (i.e., green needle < senescent needle < needle litter). Surprisingly, several inhibitory effects observed on filter paper were also found or even amplified when natural soil was used as a substrate, highlighting that soil microorganisms do not necessarily limit the negative effects of VOC released by P. halepensis on herbaceous target species. 相似文献